Hello all, I recently finished the initial version of my Onshape featurescript belt calculator. This is my first ever featurescript project, so I’m excited to be sharing it with the FRC community.
You can add the featurescript belt to your toolbar by searching “FRC Belt Calculator” in the add featurescript menu in Onshape. You can also find the document itself, and the accompanying configurable parts, under the name “FRC Belt Calculator - Alex Kempen”.
- Create GT2 and HTD belts based on the number of teeth of the belt, and the teeth of your two pulleys
- You can also enable belt teeth, although this is very performance intensive and has a significant impact on regeneration times
- Choose to only allow belts sold by VEXpro or REV
- Position the belt by selecting a point or mate connector for the first pulley, and an axis or point (circular face or edge, point, or mate connector) for the second pulley to orient towards
- You can also enter an offset for the belt, which is measured from the center of the belt automatically
- You can also choose to measure the offset from the side of any inserted VEXpro or Custom pulleys (except Vexpro pinions)
Automatically choose the belt size closest to the distance between your two positioning selections
- Can also choose to get the next largest or next smallest belt
- The automatic belt selector will also honor COTS belt only selections; for example, locking belt sizes to VEXpro belts only will cause the automatic selector to choose from only VEXpro belts
Automatically display the center to center distance of the belt, and warns the user if the belt center to center does not match the distance between selections
Insert and configure custom pulleys optimized for 3D printing, based on a modified version of @Ty_Tremblay’s MKcad configurable pulleys
- Enable and configure the pulley width, flange width, bore type, and bore diameter of each custom pulley
- You can also insert standard VEXpro pulleys and pinions, although this is not typically recommended since COTS parts should usually stay out of part studios
- Choose whether to make the belt and configured pulleys one composite part, to make assembling multiple belt runs more straightforward
These features should greatly improve upon the traditional belt workflow by removing the need to use a third party belt calculator like the WCP belt calculator to get appropriate belt center to center distances.
I’ve also created several configurable parts which may be of use, all of which can be found in the FRC Belt calculator document. Most notably, I’ve created a configurable belt, which should allow you to place standard belts into assemblies directly.
You can also find an updated version of @Ty_Tremblay’s MKcad configurable pulley generators, where I’ve merged the GT2 and the HTD versions into one, standardized the options between them, and changed some of the behind the scenes values to work better for featurescript.
Furthermore, I have also created configurable part studios of all of the VEXpro GT2 and HTD pulleys. There is one with all of the VEXpro GT2 pinions and pulleys, one with all of the VEXpro HTD pulleys for 9mm wide belts, and one with all of the VEXpro HTD pulleys for 15mm wide belts. These should make the process of finding the appropriate VEXpro pulley to insert into an assembly a much more straightforward experience.
Thanks to Ernie Huerta for creating the original Creo belt calculators which inspired this one. Thanks to Andrew Kempen for helping me with some of the automatic belt selector code, and to Everen Wegner for helping with bug testing and refining the UI design.
If you have any feedback or suggestions for improvement, please let me know. I hope you enjoy using the calculator!